SNAP Policy Database Documentation


Supplemental Nutrition Assistance Program (SNAP) benefits are federally funded, but the program is administered in partnership with the States. Until the mid-1990s, there was a uniform national standard for SNAP eligibility and benefit levels, with little State variation in SNAP administration. Variation in State-level program administration and eligibility guidelines increased dramatically due to the 1996 welfare reform legislation and subsequent legislative and regulatory changes. Since the mid-1990s, States have been granted more flexibility in the way they administer SNAP.

The SNAP Policy Database provides a central source of information on State policy choices over time to capitalize on the research opportunities created by these natural policy experiments. It includes information on State-level program policies related to eligibility criteria, recertification and reporting requirements, benefit issuance methods, availability of online applications, use of fingerprinting, and coordination with other low-income assistance programs.

The information in this database can be used to study factors that influence household SNAP participation and to improve estimates of the effects of SNAP on a variety of outcomes, such as household food spending, health status, and dietary intake.

The SNAP Policy Database is updated every four years, subject to data availability.

Scope/Coverage of Data

Monthly data are provided for all 50 States and the District of Columbia from January 1996 through December 2020.


The database contains variables that relay information on a variety of State policy options, drawing on policy information from many sources. A primary source is USDA’s Food and Nutrition Service (FNS), which provides publicly available information through the SNAP State Options Reports and the SNAP Quality Control Data, and creates special tabulations from the SNAP National Databank. Information is also collected from USDA, FNS policy guidance memos, contracted studies, and correspondence with FNS staff. Additional information is collected from national and State policy research organizations, including reports on online applications from the Center on Budget and Policy Priorities as well as reports on State-funded food assistance programs from the National Immigration Law Center. Information from State policy manuals and news articles are also used to corroborate primary data sources. The Urban Institute initially compiled the information on State SNAP policies from 1996 to 2004 with funding from the ERS Food Assistance and Nutrition Research Program.

The methods used to create variables depend on their underlying data sources. For variables based on the USDA, FNS SNAP State Options Reports or other periodic reports, the information from the reports is compiled and any policy changes between reports are assumed to have occurred at the midpoint of the two reports. If the specific date of a policy change can be determined that date is used instead of the midpoint. The variables based on the SNAP Quality Control data or National Databank are summary statistics created in Stata. The broad-based categorical eligibility and vehicle exemption variables are created from information supplied by USDA, FNS that pinpoints the specific month of policy implementation.

A complete list of variables and further details on their construction in the SNAP Policy Database is available for download.

Strengths and Limitations

The strength of the database is that it serves as a single, authoritative source on policy changes in SNAP since 1996, when States were granted increased flexibility in program operations. ERS is able to identify the State policy choices that are most likely to influence participation and to work closely with USDA’s Food and Nutrition Service to compile and ensure the accuracy of the data.

The database can be used to:

  • Describe the differences in the State-level administration of SNAP and trends in the adoption of specific State-level SNAP policies,
  • Examine how State policies affect household-level participation in SNAP, and
  • Estimate the effect of SNAP participation on outcomes such as health and food spending by combining this data with nationally representative survey data. The SNAP Policy Database provides information on variation in program administration that can be used in estimation techniques, such as instrumental variables estimation, designed to establish a causal relationship between SNAP participation and outcomes of interest.

One limitation of the database is that errors may exist in the primary data sources used, particularly those that rely on State agency survey responses such as the FNS State Option Reports and other reports from various research organizations. An additional limitation, as noted above, is that it is not always possible to pinpoint the exact month of a policy change between periodic reports, requiring some imputations. These imputations were applied to the following variables: call, cap, oapp, vehexclall, vehexclamt, and vehexclone. Further details about the imputations are available upon request. Finally, there are time periods when information on the policy is not available. In these months, missing values are denoted by a blank cell in the Excel worksheet. The downloadable list of variables provides information on missing values for each variable.


Recommended Citation

U.S. Department of Agriculture, Economic Research Service. (2024). SNAP policy database.